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Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_13 | Pages 94 - 94
1 Nov 2015
Maloney W
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A standard is defined as something established by authority, custom, or general consent. Clearly that does not exist for ceramic on ceramic total hip replacement. A better question is: Is there any indication for a ceramic on ceramic total hip. The answer to that question should when possible be based on clinical outcome data including the value added (or not) with this more expansive technology. Ceramic on ceramic has been popularised based on its low wear. Is this clinically relevant? Probably not, based on currently available data. Both metal on highly crosslinked polyethylene and ceramic on highly crosslinked polyethylene have very low clinically documented wear rates with excellent outcomes in multiple studies. In addition, ceramic on ceramic bearings are more sensitive to implant position. Whereas polyethylene may tolerated edge loading and impingement, ceramic bearings are less likely to do so. Dislocation remains one of if not the top reason for early revision. Even with newer ceramics, there are still less options to fine tune hip stability with ceramic on ceramic bearing surfaces. When looking at the overall, risk of revision, Bozic et al concluded that hard bearings provided no benefit in terms of risk reduction of revision. Considering their higher cost, they questioned the use of these products especially in the 65 and older age group. Looking at the Australian Registry, the cumulative percent revision for ceramic-ceramic THA was 5.7% at 11 years compared to 5.1% for metal on crosslinked poly. The hazard ratio (adjusted for age and gender) was 1.09 in favor of ceramic on poly and the difference was highly significant (p=0.012). When one take into account the increased cost of ceramic on ceramic bearings, it is hard to make a case for ceramic on ceramic bearings. Any use of ceramic on ceramic bearings would have to be based on the hypothesis that in the long run in young active patients they may provide an advantage. This is a hypothesis with no data to support it currently


BACKGROUND CONTEXT. Ceramic bearings are widely used in total hip arthroplasty (THR) along with metal and polyethylene bearings. There were several studies in past few years evaluating the advantage of one over the other. The young population with high activity levels has an increased risk of wear debris production at bearing surface and subsequent implant failure. Recently, interest and use of a ceramics with high wear resistance has been growing. Early reports on ceramic on ceramic THR have demonstrated excellent clinical and radiological results. PURPOSE. To evaluate clinical, functional and radiological outcomes of cement-less ceramic on ceramic primary total Hip Replacement (THR) in young patients (<50 years age) with diagnosis of avascular necrosis femoral head. STUDY DESIGN. Single - centre, prospective comparative study of prospectively collected outcomes, with a minimum of 12 month follow-up. PATIENT SAMPLE. 30 patients who underwent cement-less ceramic on ceramic primary THR in young patients (< 50 years age) for avascular necrosis of femoral head. OUTCOME MEASURES. For clinical evaluation, Harris hip scores was measured pre-operatively and post-operatively at predefined intervals. For radiological evaluation, Post- operative radiographs were checked for alignment of femoral stem, loosening of stem, presence of heterotopic ossification, loosening of acetabular component at predefined regular intervals. METHOD. This study included 30 patients, who underwent cement-less ceramic on ceramic primary THR in young patients (< 50 years age) for avascular necrosis of femoral head between July 2013 to April 2015 with a minimum of 12 month follow –up. RESULTS. The mean Harris hip score in our study increased from 32.73 pre-operatively to 87.8 post-operatively at the latest follow up with 90% hips having good to excellent results. This improvement was statistically significant (p<0.005). On evaluation of alignment of femoral stem 27 stems were central (90%) and 3 stems found to be in valgus (10%) and none to be in varus position. There was no significant correlation between stem alignment and clinical outcome based on Harris hip score. Not a single case of focal osteolysis, stem loosening or heterotopic ossification was seen in our study till latest follow-up. None of the major complication was noticed during evaluation of our cases except minor chronic hip pain in one patient which did not restricted his daily living activities. CONCLUSION. In our study, we found better results of ceramic on ceramic THR for younger patients(<50 years age) comparable to previous studies with no serious complication found in any patient. Based on our study, we recommend ceramic on ceramic THR for younger patients in the age group of less than 50 years of age. We need a study of large sample size with long term follow up to further confirm the findings of our study


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_15 | Pages 273 - 273
1 Mar 2013
Steppacher S Tannast M Murphy S
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Young patients have been reported to have a higher risk of revision following total hip arthroplasty than older cohorts. This was attributed to the higher activity level which led to increased wear, osteolysis, and component fracture. We prospectively assessed the clinical results, wear and osteolysis, the incidence of squeaking, and the survivorship of ceramic on ceramic THA in patients younger than 50 years (mean age of 42 [18–50] years). The series included 425 THAs in 370 patients with 368 hips followed for a minimum of 2 years (mean 7.1 years, range 2–14 years). All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper. No osteolysis was observed in any uncemented construct. There was osteolysis around one loose cemented femoral component. The survivorship for reoperation for implant revision was 96.7%. There were only two acetabular liner fractures (0.47%) and one femoral head fracture (0.24%). Two of the three fractures involved a fall from a significant height. There were no hip dislocations. Five patients (1.17%) noted rare or occasional squeaking. None had reproducible squeaking. In summary, the current study shows that ceramic-on-ceramic THAs in the young patient population are extremely reliable with a very low revision rate and an absence of wear-induced osteolysis. In addition, it shows that both bearing fracture in this young patient population typically occurs with polytrauma and squeaking issues that have been raised relative to ceramic bearings occur very rarely with the flush-mounted ceramic liner design used in this study


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_12 | Pages 75 - 75
1 Jul 2014
Murphy S
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While crosslinked polyethylene has reduced the rate of wear and osteolysis in THA, osteolysis still occurs and taper-corrosion induced wear has become recognised as an increasing problem especially when larger diameter metal bearings are used. Long-term follow up studies of newer polyethylene bearings continue to lag those of ceramic-on-ceramic bearings by several years.

Ceramic-on-ceramic (CoC) bearing surfaces have consistently demonstrated reliable clinical results with when coupled with appropriated designed femoral stems and acetabular shells and have been shown to exhibit virtually no risk of adverse biologic reaction. Further, CoC bearings have not been associated with corrosion-induced adverse tissue reactions that occur with metal taper junctions.

Revisions for squeaking have been associated with specific designs and materials, including the use of a titanium elevated metal rim on the acetabular side, and more flexible femoral components made of a beta-titanium alloy (TMZF) which had thin necks and relatively small tapers.

Multiple clinical studies document excellent long-term survival of CoC bearing couples in young patients with revision for any reason as the primary endpoint. Our own experience with 341 hips in patients under 50 with 2–15 years and average 9.1-year follow up demonstrates a 95% overall survivorship (revision for any reason) at 13 years.

CoC bearings continue to show excellent durability in young, high demand patients with an absence of osteolysis in any case. CoC bearings continue to represent an excellent alternative to bearing couples containing polyethylene.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_9 | Pages 50 - 50
1 May 2016
Moon K Ryu D Seo B
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A ceramic is currently considered as the most ideal articulation in primary THA. The authors evaluated clinicoradiographic results and complications of cementless THA with 3rd generation of ceramic bearing. From April 2001 to January 2008, 310 primary THAs were performed in 300 patients using 3rd generation of ceramic bearing. In results, Harris hip score at last follow up was improved to an average of 95.4 points from 51.6 points preoperatively. In all cases, fixations around implants were stable and there was no osteolysis. Complications were dislocations, squeaking, ceramic femoral head and liner fracture. Our outcomes using cementless THA with 3rd generation of ceramic articulation were satisfactory, but more clinical study and investigation will be necessary to reduce complications


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_1 | Pages 7 - 7
1 Feb 2015
Barrack R
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The use of hard-on-hard bearings, including ceramics peaked in the mid 2000's and has seen rapid decline since that time. Ceramics are not new to the market place but have had a 40 year history outside the U.S. The basis for renewed enthusiasm for ceramics included improved manufacturing, improved taper tolerances, higher strength, and lower wear. In spite of the major improvements concerns have been expressed with new generation ceramics by the experts and thought leaders in the field. The major concerns included complications related to modularity, continued problems with fracture and consequences of fracture, limited surgical options, and squeaking and impingement. The conclusion of one review article was that “although ceramics show promise as a lower wear articulation, manufacturing and design modifications and improvements will continue in an attempt to address the substantial concerns that persist”. Modifications have indeed occurred. The question is rather all of these concerns have been addressed and the answer is no. One proposed solution was a hybrid material of Alumina and Zirconia (Delta Ceramic). The advantages included higher strength, lower wear, more options and possibly less squeaking. Unfortunately the modest material improvements did not begin to overcome the obstacles to adopting this technology. High on this list is the problem with cost with the current health care environment unwilling to pay for expensive new technology that does not have proven value. A 2nd major issue is new technology must account for variability in surgeon performance in maximising margin for error. The medical legal environment is unforgiving of failure of new unproven options. Most of the old issues with ceramics have not been completely resolved. Delta Ceramic in particular, has increased cost with no demonstrated benefit. A major problem is there is no known problem with metal or ceramic against cross-linked polyethylene bearing in terms of wear or osteolysis in the 10–15 year time frame. Among all the bearing articulations, metal-on-cross-linked performs the best. The persistent vexing problems with ceramics include impingement, liner breakage, and squeaking. Ceramic components do not tolerate component malposition which increases wear and squeaking. The problem is that a substantial percentage of hip replacements are put in outside of the ideal radiographic zone even at specialty centers. Breakage continues to be a problem especially with liners. There is also a need for complete rim exposure for concentric placement with impaction of liners which makes ceramics less compatible with small incision surgery. The problem of squeaking has not been solved by Delta Ceramic. Originally a case report appeared in the literature of squeaking with Delta Ceramic. Since that time a large scale study has showed that only 69% of Delta Ceramic hips were silent with up to 13% being associated with reproducible squeaking. While a new generation of ceramics are better than the earlier generation and have lowered the fracture risk and increased intraoperative options, the current generation ceramics still provide far fewer options than a standard metal-on-cross-linked total hip. The current generation metal-on-cross-linked total hips have 10–15 year results that cannot be improved upon in terms of wear and osteolysis. Other unsolved problems include breaking, chipping and squeaking. Ceramic-on-ceramic is less tolerant of suboptimal position which leads to impingement, edge loading, and an increased incidence of squeaking. Until all of these problems are successfully addressed, ceramic-on-ceramic cannot be advocated for widespread use


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_1 | Pages 6 - 6
1 Feb 2015
Perka C
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The leading cause for total hip arthroplasty (THA) revision remains aseptic loosening due to bearing wear. The younger and more active patients currently undergoing arthroplasty present unprecedented demands on THA-bearings. Ceramic-on-ceramic (CoC) bearings have consistently shown the lowest wear rates. The recent advances, especially in alumina CoC bearings, have solved many past problems and produced preferable results in vitro.

Alumina ceramics are extremely hard, scratch resistant, biocompatible, offer a low coefficient of friction, superior lubrication and lower wear rates in comparison to other bearings in THA. The major disadvantage of ceramics used to be fracture. The new generation of alumina ceramics, has reduced the risk of ball fracture to 0.03–0.05%. The risk for liner fracture is even lower.

Assuming an impingement-free component implantation, CoC bearings have major advantages over other bearing combinations. Due to the superior hardness, CoC bearings produce less third body wear and are virtually impervious to damage from instruments during the implantation process.

A complication specific to CoC bearings is squeaking. Squeaking occurs if the friction in the joint articulation is sufficient to excite vibrations to audible magnitudes (due to loss of lubrication). The high range of reported squeaking (0.45% to 10.7%) highlights the importance of correct implant position. If a correct implant position can be guaranteed, then squeaking is rare and without clinical significance.

The improved tribology and presumable resulting implant longevity make CoC the bearing of choice for young and active patients. Especially the alumina matrix (Biolox delta) offers increased burst strength and greater fracture toughness.


Orthopaedic Proceedings
Vol. 97-B, Issue SUPP_13 | Pages 93 - 93
1 Nov 2015
Murphy S
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Properly designed ceramic-on-ceramic total hip arthroplasty has consistently shown excellent clinical outcomes without the problems associated with crosslinked polyethylene bearings such as liner dissociation, debris associated osteolysis, polyethylene fracture, clinically measurable wear, and taper-corrosion associated adverse tissue reaction when metal heads are used. The recognition of these results has been affected by the confusion with the poorer results of designs with elevated metal rims especially when coupled with the use of femoral components made of beta-titanium alloys. Our clinical experience, now at 18 years, with flush mounted liners and Ti-Al6-V4 stem and cup alloy demonstrate consistently excellent outcomes without osteolysis or ALTR. Ceramic-Ceramic THA remains the gold standard for the young active patient.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_3 | Pages 69 - 69
1 Jan 2016
Murphy S Le D Murphy W
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INTRODUCTION. Young patients (< 50 years old) have been reported to have a higher risk of revision following total hip arthroplasty (THA) than older patient cohorts, possibly to due higher activity, a higher incidence of deformity and greater probability of prior surgery. Ceramic-on-ceramic bearing surfaces have been proposed for use in young and active individuals due to their low wear, low risk of adverse biologic reaction, and long-term survivorship. We assessed the clinical results and long-term survivorship of uncemented ceramic-on-ceramic THA in a young patient population. METHODS. Between August 1999 and December 2007, 220 total hip arthroplasties in 191 patients under 50 years of age at the time of surgery were performed using alumina ceramic-ceramic bearings as part of a prospective, non-randomized study. All patients received uncemented acetabular components with flush-mounted acetabular liners using an 18 degree taper, and uncemented femoral components. The average patient age at the time of surgery was 42.1 ±7.2 years (range: 17.4 years to 49.9 years), and the average time to follow-up was 10.1 ±2.4 years (range: 4.2 years to 15.2 years). We evaluated implant-related complications and performed Kaplan-Meier analyses to determine survivorship of the THA components with revision for any reason as the endpoint. RESULTS. There were no dislocations or failures due to osteolysis or aseptic loosening. There was one patient death not related to the THA procedure. Through 15-years, the Kaplan-Meier survivorship of all components was 94.9% (CI: ±8.0) with 8 revisions (3.6%) of either the cup, the stem, or both. For the acetabular component, the 15-year survivorship was 97.0% (CI: ±6.1) and included 4 revisions (1.8%), and 98.1% (CI: ±1.9) for the femoral component including 4 revisions (1.8%). One patient had both the femoral and acetabular components revised. There were two liner fractures (0.59%) and one head fracture (0.3%), two of which were sustained as a result of a fall from significant height. There were three failures of osseointegration (1.3%), and one acetabular component dislodged (0.4%) immediately following surgery. Two patients reported non-reproducible squeaking. One hip was revised at an outside institution for unknown reasons. Using the National Institutes for Health and Clinical Excellence (NICE) guidelines, our results are well within the 1% per year acceptable failure rate for this young patient population (acetabular components: 0.1% per year, femoral components: 0.1% per year, all revisions: 0.2% per year). From our experience, ceramic-on-ceramic THA in patients less than 50 years of age is very reliable with a low revision rate and absence of wear-related osteolysis. Component fracture typically occurs with high-energy trauma, and squeaking occurrence is rare in the flush-mounted ceramic liners used in our study. CONCLUSION. Total hip arthroplasty in young patients demonstrates excellent survivorship when uncemented titanium implants are coupled with ceramic-ceramic bearings


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_22 | Pages 23 - 23
1 Dec 2016
Lee G
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While total hip arthroplasty (THA) has been shown successful at relieving pain and improving function in patients with coxarthrosis, wear and instability remain leading causes for revision surgery. Highly crosslinked polyethylene (HXPE) has significantly reduced wear and osteolysis but volumetric wear associated with the use of larger diameter ball heads may be an issue in the long-term. Finally, concerns with femoral taper corrosion have increased the utilization of ceramic ball heads in recent years. Ceramic on ceramic articulations are optimised for both minimizing implant wear and instability. It is biocompatible, wettable, and possesses the lowest in vitro and in vivo wear rates among all bearing couples. In fact, wear rates are lowest when the ceramic ball head size is maximised. Additionally, modern ceramic on ceramic THA designs have had an excellent clinical track record with low rates of loosening, failure, and no reports of osteolysis in even highly active, young patients. Concerns with ceramics center around issues related to fracture risk, squeaking, and cost. While the phenomenon of squeaking remains poorly understood, the reliability of ceramic implants have steadily improved with better materials, design, and manufacturing. The fracture risk for modern pure alumina implants and the newer alumina matrix composite ceramics are 1 in 5000 and 1 in 100,000, respectively. The advantages of ceramic on ceramic THAs will not be realised on every patient and therefore, should be selectively used. However, with expected increases in life expectancy and more young, active patients undergoing THA, ceramic on ceramic THA should be strongly considered in patients under age 60 years


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXIX | Pages 25 - 25
1 Sep 2012
Chana R Tilley S Facek M Walter W Zicat B Walter W
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Aim. Alumina ceramic on ceramic bearings in total hip arthroplasty (THA) may reduce the prevalence of osteolysis due to its properties of low wear and chemical inertness. This is critical in the younger patient population as they place increased demands over a longer period. This study reports on the clinical and radiographic outcomes of a series of modern cementless ceramic on ceramic THA at a minimum of 10 years in this younger group. Method. A series of 120 consecutive third generation ceramic cementless THA were performed at a single centre in 110 patients from 1997 to 1999. The average age of the patients at the time of surgery was 45 years (20 to 55 years). All procedures were carried out via the posterior approach using the same implant by the two senior authors. Results. At 10 years, 4 patients had died and 6 were lost to follow-up (5%). The mean Harris Hip Score was 94.7 points. All surviving implants analysed radiographically had evidence of stable bony ingrowth, with no cases of osteolysis. Wear rates were undetectable. There were 3 revisions (2.5%). One stem was revised following periprosthetic fracture, one stem was revised to facilitate a femoral shortening osteotomy. One cup was revised for anterior impingement causing psoas tendonitis. There was one incident of intraoperative ceramic liner chipping, which was changed without complication. There were no postoperative bearing fractures. Two patients reported intermittent squeaking at extreme hip flexion and internal rotation, the hips otherwise functioned well. The survival for both components with revision for any cause was 97.5%. Conclusion. Alumina ceramic on ceramic bearings in cementless primary THA in this series have resulted in good clinical and radiographic outcomes with low wear rates and excellent function in the demanding younger patient group at 10 years


Objectives. Total hip replacement is increasingly being conducted in younger and more active patients, so surgeons often use bearing surfaces with improved wear characteristics, such as ceramic on ceramic. The primary objective of this study was to determine if survivorship for a BIOLOX® delta ceramic on delta ceramic couple used with the PROCOTYL® L acetabular cup is significantly different from all other cementless cups in a large arthroplasty registry. The secondary objective of this study was to analyze patient reported outcomes measures (PROMs) of the subject cup with a minimum five year follow-up. Methods. Patient demographics and survivorship data was collected from the National Joint Registry of England, Wales, Northern Ireland, and the Isle of Man (NJR) database for all total hip replacements performed with the PROCOTYL® L cup used in combination with a delta-on-delta articulation, as well as for all other cementless cups. Survivorship data was compared for all revisions and cup revisions only and data was adjusted to exclude metal on metal articulations. The hazard ratio of the subject system to all cementless cups was also calculated with the Cox Proportional Hazards model. Patients with the subject components implanted for a minimum of five years completed Oxford Hip, EQ-5D, and EQ VAS score questionnaires. Results. The patient demographic data collected for the subject components and all cementless cups is provided in Figure 1. Six-year survivorship for the subject cup (98.6%) was similar to survivorship for all cementless cup revisions in the NJR database (98.5%), as seen in Figure 2. When the cup alone was revised, six-year survivorship of the subject cup (98.6%) and all NJR cementless cups (98.5%) was also similar. However, the subject cup survivorship remained at 98.6% from 4 to 6 years post-implantation, while survivorship for all cementless cups decreased slightly from years 4 to 6. The similarities between the revision risk of the subject system and all cementless cups in the NJR can be seen in the Cox Proportional Hazards model for revision risk ratios provided in Figure 3. Patients with the subject cup implanted for an average of 5.88 years reported Oxford Hip, EQ-5D, and EQ VAS scores of 39.60 ± 10.78, 0.801 ± 0.259, and 75.49 ± 19.25, respectively. Conclusions. The subject acetabular cup with a ceramic on ceramic articulation exhibited similar survivorship to all other cementless acetabular cups, excluding those with metal on metal bearings, in the NJR. Patients implanted with the subject system for an average of 5.88 years reported what are considered satisfactory Oxford Hip, EQ-5D, and EQ VAS scores. This survivorship and PROMs data is the first report of mid-term outcomes with the subject components


Orthopaedic Proceedings
Vol. 100-B, Issue SUPP_5 | Pages 41 - 41
1 Apr 2018
Taki N Mitsugi N Mochida Y Yukizawa Y Sasaki Y
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Introduction. Long term results of Total Hip Arthroplasty (THA) are affected by wear of articulation. Ceramic on ceramic articulation have been used especially for young patients because of its low wear and bio-inert property. However, because of its hardness, it is concerned that ceramic fracture, chipping, or squeaking might happen with ceramic on ceramic articulation. Objective. The purpose of this study was to investigate over 10-years clinical and radiographic results of ceramic bearing cementless THA. Methods. Evaluation was performed in 60 patients (68 joints) who underwent primary cementless THA from May 2003 to April 2007. Mean age at surgery was 59 years. Mean follow up period was 11.2 years. Forty-nine patients were female. Mean BMI at surgery was 24.0 kg/m. 2. Fifty-one patients had osteoarthrosis, 6 patients had osteonecrosis, 2 patients had rheumatoid arthraitis, and 1 patient had PSS. A 28mm-size femoral head was used in all patients. Clinical evaluation was performed with Japanese Orthopaedic Association Hip Score (JOA score). Radiographic results were evaluated with standard bilateral hip radiograph in supine position. Results. Mean clinical score at surgery was 45 (pain: 13/40, ROM: 12/20, gait: 9/20, ADL: 12/20). Mean clinical score at final follow up was 92 (pain: 39/40, ROM: 17/20, gait: 17/20, ADL: 18/20). Pain score was dramatically improved from 13 to 39 (maximum pain score: 40). One stem was revised because of recurrent dislocation. Two other patients experienced one time dislocation during follow up. One stem showed 5mm of subsidence. ALL cups and stems showed bone ingrowth at final follow up. Cortical hypertrophy was seen in 17 joints. However, there was no patient complained thigh pain. Stress shielding was seen in 55 joints (81%). First, second and third degree of stress shielding were seen in 12, 40, and 3 joints, respectively. Most of the female patients who had surgery at the age over 60 years showed second and third degree of stress shielding. There was no measurable wear. No osteolysis was found around the implants. There were no ceramic fracture, chipping, and squeaking. Conclusion. This study demonstrated excellent clinical and radiographic results of ceramic bearing cementless THA. Excellent long term results will be expected with this system


Orthopaedic Proceedings
Vol. 102-B, Issue SUPP_8 | Pages 22 - 22
1 Aug 2020
Sandoval C Di Bella J Dragan A de Guia N Webster G Dunbar MJ Bohm E Yu C
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Revision is a key negative outcome of joint replacements. The purpose of this abstract is to present revision risk curves for hip and knee replacements based on the most recently available national data sources. Having a better understanding of determinants of revision risk can help inform clinical and health care system improvements. We explored revision risk of primary joint replacement stratified by key clinical, prosthesis, and surgeon-level factors using data from three databases managed by CIHI: the Canadian Joint Replacement Registry (CJRR), the Discharge Abstract Database, and the National Ambulatory Care Reporting System. To investigate early revisions, we used Kaplan-Meier analysis stratified by demographic factors to determine the risk of revision within up to five years of primary surgery. This analysis identified the primary cohort from the CJRR from April 1, 2012 to March 31, 2017 and was limited to mandatory reporting provinces (British Columbia, Manitoba and Ontario) to ensure maximal coverage of prosthesis information. Bearing surface was obtained from the International Prosthesis Library maintained by the International Consortium of Orthopaedic Registries (ICOR) and the International Society of Arthroplasty Registers (ISAR). The total revision risk cohort contained 283,620 primary surgeries, of which 5,765 (2%) had at least one revision. For total hip arthroplasties, revision risk at the end of the follow-up period did not differ by age, by sex or across bearing surface (metal on cross-linked polyethylene [XLPE], ceramic on XLPE, ceramic on ceramic, metal on non-cross-linked polyethylene). For hemiarthroplasties in hip fracture patients, cement fixation was significantly associated with decreased revision risk. Surgeon volume had a positive effect on survivorship with cementless fixation (2.7% at one year [95% CI 2.3%, 3.1%] for high-volume vs 3.2% [2.7%, 3.7%] for low-volume). However, surgeon volume did not have an effect on survivorship with cemented fixation (2% at one year [95% CI 1.3%, 2.6%] for high-volume vs. 2% [1.4%, 2.6%] for low-volume). For total knee replacements, revision risk increased with decreasing age and male sex. For patients aged 75 and older, four-year revision risks were 1.5% (95% CI 1.3%, 1.7%) for women and 2.0% (1.7%, 2.3%) for men, but for patients under 55 years old, they were 4.3% (3.7%, 5%) for women and 5.9% (4.9%, 6.9%) for men. Additional results from the upcoming 2019 CJRR annual report, including data up to March 31, 2018, will be presented. Revisions represent a key failure of the primary replacement, they are costly to the health care system and negatively affect patients' quality of life. CJRR's coverage is currently 72%, increased coverage and follow-up time will allow increasingly comprehensive reporting on hip and knee prostheses in Canada. Future work in this area involves exploring additional prosthesis attributes for stratification of revision risk curves and calculation of hazards ratios adjusted by age and sex


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXV | Pages 26 - 26
1 Jun 2012
Su E Chotai P
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Introduction. Alumina Ceramic liners are increasingly used in patients undergoing Total Hip Replacement (THR). The rate of fracture of ceramic liner is decreasing with improved manufacturing techniques from 1. st. to 3. rd. generation alumina-ceramic liners. We report the first case of a fracture of a modern, 4. th. generation alumina bearing ceramic liner, which incorporates a metal sheath to help avoid fracture. Our case is a 60 years old female presenting two years and three months after a bilateral total hip replacement using Stryker Trident cup, securfit stem and alumina on alumina bearing ceramic liner. Ceramic liners are commonly used, especially in young patients because of their excellent biocompatibility, low wear rate and superior tribology. Although fracture of ceramic liner is a less common complication of modern total hip arthroplasty, it is a major concern with the use of ceramic on ceramic THR, the reason being brittleness of ceramic. Cases of 3. rd. generation ceramic liner fracture have been reported which might be associated with impingement due to excessive anteversion of the socket in Asian patients who habitually squat. Habitual squatting, sitting cross legged and kneeling were not characteristic of this case. Methods. The patient presented with complains of mechanical grinding in left hip. She also reported a past history of clicking sound from left hip on extension of left hip and long stride gait. There was no history of trauma or fall. On examination she had a nonantalgic gait and left hip had audible and palpable crepitations. The range of motion on left hip was intact with no subluxation. Right hip was symptom free and examination did not detect any abnormalities. Evaluation & Results. Radiographs of left hip revealed eccentric positioning of the head [Fig. 1] within the socket and excessive anteversion of the socket, which likely caused edge-loading in extension, leading to catastrophic failure in form of fracture of ceramic liner on left hip. She was treated with revision surgery using polyethylene liner with metal head. Intra-operative findings confirmed the ceramic liner fracture [Fig. 2] and revealed impingement of the metal neck against the metal rim of the liner. Discussion & Conclusion. Although ceramic on ceramic hips have excellent wear properties, it is subject to fracture due to its brittle nature. This can lead to catastrophic failure with edge loading. In this case, the alumina-ceramic liner fractured; despite of being surrounded by a metal rim to prevent fracture. It fractured at the anterior edge, which is where it was loaded in extension. We believe that careful attention must be paid not only to inclination, but version of the socket, so as to avoid this complication. Other factors which might lead to such complication are obesity, high activity level, improper manufacturing teachniques for ceramic liners and entrapment and impingement of a micromm sized foreign body between ceramic liner and prosthetic head which initiates wear


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_8 | Pages 24 - 24
1 May 2014
Padgett D
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Due to issues related to osteolysis which became increasingly evident in the 1990's, approaches to combat wear focused upon either improving ultra-high molecular grade polyethylene or to abandon it and employ alternative bearings: metal upon metal or ceramic upon ceramic (COC). Ceramics have played a role in hip bearings for decades with much of the experience coming from Europe. While there is consistent evidence of low wear rates in this bearing couple due to its surface hardness, wettability and resultant low friction, problems unique to this bearing couple were noted: a small but real incidence of fracture, surface damage due to metal transfer and stripe wear as well as the unique issue of squeaking. What we have learned is that these hard bearings (either COC or Metal on Metal) despite being able to use larger diameter heads, are exquisitely sensitive to component position and orientation. With the tremendous improvements in 2nd and now 3rd generation crosslinked polyethylenes demonstrating vastly reduced wear rates and having none of the issues of fracture, stripe wear, or squeaking, it remains unclear what role ceramic bearings have in modern use. Until the aforementioned issues are resolved, ceramic on ceramic bearings in the young patient should be used with caution. Ceramic-on-ceramic total hip arthroplasty: incidence of instability and noise


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_10 | Pages 158 - 158
1 May 2016
Graves S Lorimer M Bragdon C Muratoglu O Malchau H
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Introduction. Infection remains a serious complication following primary total hip arthroplasty (THA). Many factors including primary diagnosis, comorbidities and duration of procedure are known to influence the rate of infection. Although the association between patient and surgical factors is increasingly well understood, little is known about the role of the prosthesis. This analysis from the Australian Registry (AOANJRR) was undertaken to determine if revision for infection varied depending on the type of bearing surface used. Methods. Three different bearing surfaces, ceramic on ceramic (CoC), ceramic on cross-linked polyethylene (CoXP) and metal on cross-linked polyethylene (MoXP) were compared. The study population included all primary THA undertaken for OA using these bearing surfaces and reported to the AOANJRR between 1999 and 2013. Kaplan-Meier survivorship curves were compiled with revision for infection as the end point. Hazard Ratios (HR) from Cox proportional hazards models were used to compare revision rates. Sub analysis examining the effect of age, gender, fixation of the femoral stem and femoral head size. To ensure there was no confounding due to differences in femoral and acetabular component selection a further analysis was undertaken which compared the three different bearings with the same stem and acetabular component combinations. Results. During the study period there were 177,237 primary THA's reported to the registry that met the inclusion criteria (57,839 CoC, 24,269 CoXP and 95129 MoXP). When all procedures were included Both MoXP and CoXP had a higher revision rate for infection compared to CoC (HR 1.46 (1.25, 1.72) p<0.001 and HR 1.42 (1.15, 1.75) p=0.001 respectively). There was no difference in the revision rate for infection when MoXP and CoXP were compared. There was an age variation with the lower revision rate for infection rate being evident in patient's age 70 years or younger but not older patients. Both men and women had a lower revision rate when CoC was used. The difference was evident when a cementless femoral stem was used but not when the stem was cemented. The difference was also evident for most head sizes with the exception of 28 mm heads. CoC also had a lower revision rate for infection when the same femoral stem and acetabular component combinations were compared. Conclusion. Patients aged 70 years or less have a lower revision rate for infection when a CoC bearing is used compared to both CoXP and MoXP. This difference was independent of gender, and femoral and acetabular prostheses selection. No difference was evident if the femoral component was cemented or a head size of 28 mm was used


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 115 - 115
1 Jan 2016
Thornton-Bott P Tai S Walter W Zicat B
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Background. Total Hip Arthroplasty (THA) using the Direct Anterior Approach (DAA) is a muscle sparing approach which promotes early mobilisation of patients. It is a technically challenging approach shown to have a high rate of complications, especially during the learning curve. Here we present the results of 157 cases of THA via a DAA on a standard theatre table, with a minimum of 6 months follow-up. Materials & Methods. The authors conducted a prospective study on a group of 149 consecutive patients undergoing 157 cementless primary THAs for coxarthrosis, 8 bilateral. The same surgical technique was used in all patients, performed by the senior author WLW at a single centre. The average age of the patients at time of surgery was 69 years, 78% were female and 57% were right sided. All implants were uncemented, with bearings being ceramic on ceramic or Ceramic on highly cross-linked polyethylene. Patients were assessed clinically and radiographically pre- and post-operatively at 6 weeks, 6 months, 1 and 2 years. Intra-operatively, navigation was used to guide cup position and assess offset and leg length. Results & Discussion. At the time of the latest follow-up, 1 patient had died of unrelated cause and 8 (5%) were lost to follow-up Clinically, the mean Harris Hip Score was 91 points with 88% reporting a good or excellent result, with 5% reporting moderate to severe pain. Radiographically all patients assessed had evidence of stable bony ingrowth. There was subsidence of 2–5mm in 9 stems (6%). Osteolysis was reported adjacent to one cup and one stem. There were no dislocations. The complication rate was 4.5%. This included 2 intra-operative femoral fractures, one a minor greater trochanteric fracture not requiring fixation, the other a calcar fracture treated at time of surgery. There were 3 femoral fractures occurring on average 4 weeks after surgery all requiring revision and one stem subsidence of 10mm following a heavy fall, subsequently requiring revision for leg length discrepancy. Other complications included one non-fatal PE, a haematoma that required evacuation. We report 20 (12%) episodes of lateral femoral cutaneous nerve palsy of any severity, most of which had or were resolving at the 6 month follow-up. Kaplan Mieir survival analysis was 97.2% at minimum 6 months. Patients mobilised day of surgery or day 1 post-op, and were discharged on average day 4 post-op. Neither the intra- or post-operative fractures could be attributed to the learning curve. Similarly episodes of stem subsidence and LFCN palsy occurred spread out over the 3 years of the study. This study supports the existing orthopaedic literature reporting the benefits of the DAA for THA with reduced soft tissue damage, reduced blood loss and early mobilisation with a low incidence of dislocation. Other authors however have reported a high incidence of complications attributing them to the early learning curve. This early study of DAA using a standard theatre table has identified that complications of fracture, stem subsidence and LFCN injury can occur at any time and bear no relationship to a learning curve


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLI | Pages 110 - 110
1 Sep 2012
Nikolaou V Edwards M Bogoch E Schemitsch E Waddell J
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This prospective randomised controlled trial aims to compare the clinical and radiological outcomes of ceramic on ceramic, cobalt chrome on ultra-high molecular weight polyethylene, and cobalt chrome on highly cross-linked polyethylene bearing surfaces at a minimum of five years. One hundred and two primary total hip replacements were performed in ninety one patients between February 2003 and March 2005. All patients were younger than 65 (mean 52.7, 19–64). They were randomised to receive one of the three bearing surfaces. All patients had 28mm articulations with a Reflection uncemented acetabular component and a Synergy stem (Smith & Nephew, Memphis, Tennessee). Patients were followed up periodically up to at least sixty months following surgery. Outcome measures included WOMAC and SF12 scores. Radiological assessment included implant position, evidence of osteolysis and measurement of linear wear. Ninety seven hip replacements in eighty seven patients were available for review at a minimum of five years. Two hips were revised (one for infection and one for periprosthetic fracture), leaving a total of ninety four hips available for final review. There were no differences in age, gender, body mass index, diagnosis, level of activity, and co-morbidities between the three groups. At a minimum of five years there were no statistical differences in the clinical outcomes using the WOMAC or SF12 scores. Three patients in the ceramic group reported squeaking. Radiological evaluation revealed mean annual wear rates in the ceramic group of 0.006mm/yr, standard polyethylene of 0.151mm/yr and highly cross linked polyethylene of 0.059mm/yr. ANOVA analysis revealed these differences in wear rates to be significant (p<0.0001). In the mid term there are no differences in clinical outcome between ceramic on ceramic, cobalt chrome on ultra-high molecular weight polyethylene, and cobalt chrome on highly cross-linked polyethylene bearing surfaces in total hip arthroplasty. Ultra high molecular weight polyethylene has a significantly greater annual linear wear rate than highly cross-linked polyethylene


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVIII | Pages 107 - 107
1 Sep 2012
Waddell JP Nikolaou V Edwards M Bogoch E Schemitsch EH
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Purpose. This prospective randomised controlled trial aims to compare the clinical and radiological outcomes of ceramic on ceramic, cobalt chrome on ultra-high molecular weight polyethylene, and cobalt chrome on highly cross-linked polyethylene bearing surfaces at a minimum of five years. Method. One hundred and two primary total hip replacements were performed in ninety one patients between February 2003 and March 2005. All patients were younger than 65 (mean 52.7, 19–64). They were randomised to receive one of the three bearing surfaces. All patients had 28mm articulations with a Reflection uncemented acetabular component and a Synergy stem (Smith & Nephew, Memphis, Tennessee). Patients were followed up periodically up to at least sixty months following surgery. Outcome measures included WOMAC and SF12 scores. Radiological assessment included implant position, evidence of osteolysis and measurement of linear wear. Results. Ninety seven hip replacements in eighty seven patients were available for review at a minimum of five years. Two hips were revised (one for infection and one for periprosthetic fracture), leaving a total of ninety four hips available for final review. There were no differences in age, gender, body mass index, diagnosis, level of activity, and comorbidities between the three groups. At a minimum of five years there were no statistical differences in the clinical outcomes using the WOMAC or SF12 scores. Three patients in the ceramic group reported squeaking. Radiological evaluation revealed mean annual wear rates in the ceramic group of 0.006mm/yr, standard polyethylene of 0.151mm/yr and highly cross linked polyethylene of 0.059mm/yr. ANOVA analysis revealed these differences in wear rates to be significant (p<0.0001). Conclusion. In the mid term there are no differences in clinical outcome between ceramic on ceramic, cobalt chrome on ultra-high molecular weight polyethylene, and cobalt chrome on highly cross-linked polyethylene bearing surfaces in total hip arthroplasty. Radiologically there was little evidence of linear wear in the ceramic group. Cobalt chrome on ultra high weight polyethylene has a significantly greater annual linear wear rate than that of cobalt chrome on highly cross-linked polyethylene